Side return extensions in Chiswick

Covering Chiswick

Chiswick sits 6 miles west of London, with Acton 1 miles to the north-west and Barnes 1 miles to the south.

Homes in London

Much of London’s housing is Victorian and Edwardian terraces, which is why side return extensions, rear dormers and mansards are so common. Many streets are in conservation areas, and several boroughs use Article 4 directions that remove some permitted development rights.

What is a side return extension?

Side returns are small in area but heavy in detail: party walls, a glazed roof, and steelwork to take out the original back wall. We design the roof for light and drainage, agree the party wall process early, and keep the work tidy because access is often through the house.

Structural steel to remove the side wall
Glazed or solid roof with rooflights
Underfloor heating ready screed if wanted

How much does a side return extension cost in Chiswick?

Typical ranges for side return extensions. Ground conditions, access and specification move the final figure, which we fix in writing before work starts.

Side return extensions	Guide price incl. VAT
Standard specification	£3,350 to £3,700 per m²
Good specification	£3,700 to £4,150 per m²
High specification	£4,150 to £4,550 per m²

Planning and building rules in Chiswick

English projects need planning clearance from the local council, building regulations sign-off from building control, and party wall notices where the work is on or near a shared boundary. We prepare and manage all three.

In England a single-storey rear extension can often go ahead under permitted development: up to 3 m deep on an attached house or 4 m on a detached one, no higher than 4 m, with eaves no higher than 3 m within 2 m of a boundary. Deeper extensions, up to 6 m or 8 m, need prior approval from the council first.

What should Chiswick homeowners check first?

Access is often through the house, so we plan deliveries and protect floors.
Glazed roofs need careful detailing against the neighbour’s wall.

What are the steps?

Start with a conversation. A short call or the online form is enough for us to understand what you want to build.
Survey at your house. We look at the existing structure, services and access, and agree what the design needs to achieve.
Drawings, approvals, written quote. We prepare the design, apply for the approvals it needs, and give you a fixed price in writing.
Construction and completion. One site lead co-ordinates every trade through to the building control certificate.

Side return extensions: common questions

How much does a side return extension cost?

Usually about £3,350 to £4,550 per square metre including VAT, which works out at around £35,000 to £55,000 for a typical side return before the kitchen.

Will I need a party wall agreement?

Most likely, because the new wall usually sits on or near the boundary. We serve the notices and work with your neighbour’s surveyor if one is appointed.

Do you work in Chiswick?

Yes. Chiswick is within our coverage for side return extensions, along with nearby Acton and Barnes.

Side return extensions in nearby towns

Learn more about side return extensions, or see every project we cover in Chiswick.